Transdermal administration of a drug can provide a number of possible advantages, such as avoidance of first-pass metabolism, avoidance of gastro-intestinal irritation, sustained release, and improved patient compliance with treatment regimens. Transdermal drug delivery devices used for this purpose are typically designed to deliver a therapeutically effective amount of drug across the skin of a subject. The drug is normally incorporated into a carrier, such as a liquid, gel, solid matrix, or pressure sensitive adhesive. Reservoir type devices may include a membrane that controls the rate of drug release to the skin, while other devices may have a drug dispersed or dissolved in a matrix such as a pressure sensitive adhesive.
Drug dosages have been directly incorporated into the adhesive portion of transdermal patches where the adhesive is used to secure the patch to skin. Efforts to remove residual monomer components and the like from adhesives for contacting skin have been reported with the aim of reducing skin irritation, improving adhesive properties, such as adhesion, and/or reducing unpleasant odors.
However, there continues to be an interest in and a need for improved transdermal drug delivery devices and adhesive compositions used therein.